1½ cups crushed Ritz crackers (about 35 crackers)
2 cups grated Cheddar cheese, divided (you can use a mixture of mozzarella and cheddar or any cheese combination that you like)
4 tablespoons (½ stick) unsalted butter, melted, plus 2 tablespoons cold unsalted butter, cut into pieces
4 cups cooked elbow macaroni (about 8 ounces uncooked), drained and kept hot
2 large eggs, beaten
½ cup milk
¼ cup sour cream
¼ teaspoon salt
Preheat the oven to 350 degrees F. Lightly grease 8 cups of a 12-cup muffin pan.
In a bowl, combine the crackers, 1 cup of the Cheddar and the melted butter. Divide the mixture among the prepared muffin cups and press firmly into the bottom and up the sides.
In a large bowl, mix the macaroni with ½ cup of the Cheddar. In a small bowl, combine the eggs, milk, sour cream, cold butter pieces, and salt. Stir the milk mixture into the macaroni.
Spoon 2 tablespoons of the macaroni mixture into each cracker crust and top with the remaining Cheddar. Bake until the cheese is browned and slightly crispy, about 25 minutes. Allow the pies to cool slightly before unmolding and serving warm.